Printed circuit boards are used ubiquitously for a wide range of applications. A typical printed circuit board (or PCB) has a top and bottom surface, on which components may be affixed, such as by soldering. Between the top and bottom surfaces are a plurality of layers used to carry signals from one point on the PCB to another point. Each layer is comprised of an insulating material with conductive material disposed thereon.
Signals that begin on one layer can move to another layer through the use of vias. Vias are conductive pathways that connect signals on various layers together. If the layers of the PCB are defined as being horizontal planes, these vias are typically vertical conductive pathways. In some embodiments, the vias pass through the entirety of the PCB. In other embodiments, known as blind vias, the via is accessible on either the top or bottom surface, but does not pass through the entirety of the PCB. In another embodiment, known as buried vias, the via may connect signals on two interior layers and not be accessible on either outer surface.
In some embodiments, it may be beneficial to incorporate an antenna into the printed circuit board. However, the insulating material typically used for PCBs has very different properties than air. Most antennas are calibrated and tested with respect to air. Furthermore, higher efficiency and greater antenna operating performance may be achieved if the antenna is spaced apart from the PCB by a layer of air, rather than a different material. Therefore, it may be difficult to develop an antenna that is incorporated into a PCB that has the desired characteristics.
Therefore, it may be desirable for the antenna to be spaced apart from the PCB. However, such a configuration presents challenges regarding mechanically supporting the antenna, and providing electrical connections to the antenna. Therefore, it would be beneficial if there were a process to create a PCB with an attached antenna, where the antenna is spaced apart from the PCB itself. Further, it would be desirable if the antenna was mechanically supported by the PCB and had robust electrical connections thereto. For example, it would be beneficial if a foam dielectric layer could be used to separate the antenna from the PCB, where electrical connections were made through the foam dielectric layer.